Guide for the movable jaw of a pipe wrench



April 24, 1956 H. BRYNGE ET AL GUIDEFOR THE MOVABLE JAW OF A PIPE WRENCH Filed Nov. 10, 1954 4 Sheets-Shee't 1 April 1956 H. BRYNGE ET AL GUIDE FOR THE MOVABLE JAW OF A PIPE WRENCH 4 Sheets-Sheet 2 Filed Nov. 10, 1954 April 24, 1956 H. BRYNGE ETAL 2,

GUIDE FOR THE MOVABLE JAW OF A PIPE WRENCH Filed Nov. 10, 1954 4 Sheets-Sheet 3 April 24, 1956 H. BRYNGE ET AL GUIDE FOR THE MOVABLE JAW OF A PIPE WRENCH 4 Sheets-Sheet 4 Filed Nov. 10. 1954 United States Patent GUIDE FOR THE MOVABLE JAW OF A PIPE WRENCH Hannes Brynge and Gunnar Brynge, Fannalund, Enkoping, Sweden, assignors to Aktiebolaget B. A. H orth & Co., Stockholm, Sweden, a corporation of Sweden Application November 10, 1954, Serial No. 468,078 Claims priority, application Sweden November 14, 1953 2 Claims. (Cl. 81-101) The present invention relates to an improvement in pipe wrenches of the type in which the shank carrying the movable jaw is adjustable by means of an adjusting nut and is fitted in a guide formed in the handle carrying the fixed jaw so as to be cap-able of a limited rocking movement against the action of spring means. The object of this invention is to provide a stable construction which is easily manufactured and assembled and in which the shank is movable with the least possible friction and has an improved ability of resilient rocking movement, so that the grip of the wrench on the object gripped is more reliable.

In accordance with this invention, these objects are achieved by forming the guide with one or more holding members, to which one or more springs are attached or suspended and so arranged that they engage the lateral walls of a groove provided in one or both sides of the movable shank.

In one embodiment, the guide is U-shaped and a projection is provided at the inner wall of each of the arms of the U-shaped guide, said projection engaging a corresponding lateral groove in the shank and serving to limit the rocking movement of the shank which projection may also serve as a holder for a spring.

The accompanying drawings illustrate some embodiments of the invention.

Fig. 1 shows a Wrench in perspective view, the adjusting nut being shown in section.

Fig. 2 shows the fixed jaw with associated handle in perspective view, partly in section through the guide for the movable jaw shank.

Fig. 3 shows a part of a shank having grooves at both sides and its associated springs.

Figs. 4 and 5 show the spring in front and side elevation.

Fig. 6 illustrates a modified form of the shank, which has only one groove at one side for receiving a spring afiixed to the guide.

Figs. 7 to 12 illustrate a second embodiment, in which the guide for the shank is formed with a U-shaped crosssection.

Figs. 7 and 8 illustrate the second embodiment in perspective views similar to Figs. 1 and 2.

Fig. 9 illustrates the arrangement of the shank and the engagement of the springs with the grooves of the shank.

Fig. 10 shows a fragment of the shank in perspective view.

Fig. 11 is a cross-sectional view through the guide and the shank with the springs.

' Fig. 12 is a detail view showing a spring.

In the embodiment shown in Figs. 1 to 5, the wrench has a fixed jaw 1, attached to a handle 2 which has formed integral therewith a guide 3 for a shank 5 carrying a movable jaw 4. The shank 5 is formed with threadengaging teeth in a well-known manner and is slidably fitted in the guide 3. The shank 5 is moved by means of an adjusting nut 6 which is fitted between the guide 3 and a pair of lugs 7 projecting from the shank 2.

The shank 5 is formed with longitudinal grooves 8 and 9 on its opposite sides, each of said grooves receiving a spring 10 and 11 respectively. These springs are held in the guide 3 by means of pins 12 secured thereto. The free ends 13 and 14 of the springs engage the lateral walls 15, 16 of the respective grooves, as seen in Figs. 1 and 3.

By this arrangement, the shank 5 is advantageously mounted for resilient rocking movement and in a manner that permits easy adjustment of the shank by means of the adjusting nut 6.

The load on the adjustable jaw 4 occurring in the use of the wrench is transferred to the shank 5, in that in the embodiment of Figs. 1 to 5, the shank bears against back or forward walls of the annularly closed guide 3 but not against the pins 12 which serve only to retain the springs 10 and 11 in position.

In the modification illustrated in Fig. 6 a single spring 10' is employed. A groove 8' of the shank is made deeper in this case and ends 13', 14 of the spring 10 are bent more sharply, so that although only one spring disposed at one side of the shank is provided, the spring engages the shank practically centrally.

In the embodiment illustrated in Figs. 7 to 12 the guide for the shank 5 consists of a U-shaped part opening towards the back of the wrench and in arms 17 of which there are attached or formed or otherwise provided elongated projections or ribs 18 which extend into the grooves 8 and 9 of the shank 5. The ribs 18 serve to hold the springs 10 and 11 and also act as stops to limit the rocking movement of the shank 5. This arrangement simplifies the manufacture of the fixed jaw and handle member in that simpler operations more suitable for mass production may be employed than in the case of a guide having a closed annular cross-section. It will be understood that it is not necessary to have the projection formed with an uninterrupted elongated shape, but the rib 18 may with the same result be replaced e. g. by two lugs or pins spaced at a distance corresponding to the length of the rib 18.

The shape of the springs and their attachment in the guide are preferably such that the springs when positioned in the shank do not exert any force against the walls of the shank groove when the movable jaw is not subjected to strain, but allows the shank to be freely displaced without friction caused by tension of the springs. Suitably,

however, the spring may be arranged so that it has a certain preliminary tension, so that when the shank rocks, its movement will initially be counteracted by a predetermined resilient force, as is contemplated in the embodiment according to Figs. 3 to 5. For this purpose, the spring may be formed e. g. so that its deflexion is automatically limited whereby the spring retains the desired preliminary tension even when the movable jaw is not under strain.

In the longitudinal direction the spring may be retained by means of suitable bent portions bearing against the stop. Before insertion, the V-shaped spring has its tongues widely spaced, so that when the spring is positioned on the stop it receives a preliminary tensioning. When the wrench'is used and the shank rocks, this rocking movement will thereby be counteracted practically from its start by a relatively great resilient moment.

Having now particularly described the nature of our invention and the manner of its operation what we claim 1s:

1. In a pipe wrench in which a threaded shank carrying a movable jaw has a longitudinal groove in at least one sidewall thereof, said shank being adjustable by means of an adjusting nut, and in which a handle carries a fixed jaw and carries a guide for the shank of the movable jaw, said shank being capable of a limited rocking movement toward and away from said fixed jaw against the action of a spring, that improvement comprising at least one projection on that interior sidewall of the guide which confronts said longitudinal groove in said one sidewall of said shank, said projection extending into said groove, and said spring being mounted on said projection and having portions engaging opposite walls of said groove.

2. In a pipe wrench as claimed in claim 1, the guide being U-shaped in cross section, and said shank having a longitudinal groove in each sidewall that confronts a corresponding interior sidewall of the U-shaped guide, said projection and spring being provided on each of said interior sidewalls of the U-shaped guide, each of said projections and springs extending into the corresponding groove in the shank and engaging opposite sidewalls of said groove to limit the rocking movement of the shank.

References Cited in the file of this patent UNITED STATES PATENTS N" an 

